Multi-angle sludge lance

Abstract

A lancing crawler or head crawls along a no-tube lane (NTL) on a floor defining a reference plane oriented transverse to tubes of a steam generator, and has nozzles that generate lancing fluid jets along at least two different angles in the reference plane spaced apart by at least 45°. A rotational drive rotates the nozzles about an axis of rotation that may be offset from an axis of thrust imposed by the jets from the nozzles. An on-board sighting laser may be mounted with the nozzles, along with an on-board camera. A bladder expands to secure the lancing crawler or head between steam generator tubes adjacent the NTL. Each nozzle may include a taperlock seat. A nozzle tilt drive is configured to tilt the one or more nozzles respective to the reference plane.

We claim: 
     
         1 . A sludge lancing apparatus comprising:
 a lancing crawler or head configured to crawl along a no-tube lane (NTL) on a floor defining a reference plane oriented transverse to tubes of a steam generator; and   one or more nozzles mounted on the lancing crawler or head and configured to generate lancing fluid jets along at least two different angles in the reference plane spaced apart by at least 45°.   
     
     
         2 . The sludge lancing apparatus of  claim 1  further comprising:
 a rotational drive configured to rotate the one or more nozzles about an axis of rotation that is transverse to the reference plane over an angular range spanning the at least two different angles. 
 
     
     
         3 . The sludge lancing apparatus of  claim 2  wherein the at least two different angles in the reference plane spaced apart by at least 45° include the angles 90° and one of 30° and 150° respective to a 0° reference along the NTL. 
     
     
         4 . The sludge lancing apparatus of  claim 2  wherein the at least two different angles in the reference plane spaced apart by at least 45° include the angles 90°, 30°, and 150° respective to a 0° reference along the NTL. 
     
     
         5 . The sludge lancing apparatus of  claim 2  further comprising:
 a drive track configured to move the lancing crawler or head along the NTL; and 
 a center slide separate from the drive track on which the one or more nozzles are mounted, the center slide providing translation of the one or more nozzles respective to the lancing crawler or head. 
 
     
     
         6 . The sludge lancing apparatus of  claim 2  wherein the axis of rotation is offset from an axis of thrust imposed by the jets from the nozzles. 
     
     
         7 . The sludge lancing apparatus of  claim 2  further comprising:
 an on-board sighting laser mounted with the one or more nozzles and aligned to generate a laser beam parallel with a jet beam output by the nozzle. 
 
     
     
         8 . The sludge lancing apparatus of  claim 7  further comprising:
 an on-board camera mounted with the one or more nozzles and aligned to view along a jet beam output by the nozzle. 
 
     
     
         9 . The sludge lancing apparatus of  claim 2  further comprising:
 an on-board camera mounted with the one or more nozzles and aligned to view along a jet beam output by the nozzle. 
 
     
     
         10 . The sludge lancing apparatus of  claim 1  further comprising:
 a bladder configured to expand when filled with a fluid to secure the lancing crawler or head between tubes of the steam generator located adjacent the NTL. 
 
     
     
         11 . The sludge lancing apparatus of  claim 1  wherein each nozzle includes a taperlock seat comprising a conical seat of the nozzle that seats in a mating conical recess of a nozzle manifold. 
     
     
         12 . The sludge lancing apparatus of  claim 1  further comprising:
 a nozzle tilt drive configured to tilt the one or more nozzles respective to the reference plane. 
 
     
     
         13 . A sludge lancing method comprising:
 moving one or more nozzles along a no-tube lane (NTL) on a floor defining a reference plane oriented transverse to tubes of a steam generator; and   using the one or more nozzles, generating lancing fluid jets along at least two different angles in the reference plane spaced apart by at least 45°.   
     
     
         14 . The sludge lancing method of  claim 13  wherein the tubes of the steam generator have a hexagonal pattern and the at least two different angles in the reference plane spaced apart by at least 45° include the angle of 90° respective to a 0° reference oriented along the NTL and at least one of the angles 30°, 150° respective to the 0° reference oriented along the NTL. 
     
     
         15 . The sludge lancing method of  claim 13  wherein the tubes of the steam generator have a hexagonal pattern and the at least two different angles in the reference plane spaced apart by at least 45° include the angles of 30°, 90°, and 150° respective to a 0° reference oriented along the NTL. 
     
     
         16 . The sludge lancing method of  claim 13  wherein the generating comprises:
 positioning the one or more nozzles in a first position with the nozzles directed along a first angle of the at least two different angles; 
 with the one or more nozzles in the first position, generating a lancing fluid jet along the first angle; 
 positioning the one or more nozzles in a second position with the nozzles directed along a second angle of the at least two different angles that is at least 45° away from the first angle in the reference plane; and 
 with the one or more nozzles in the second position, generating a lancing fluid jet along the second angle. 
 
     
     
         17 . The sludge lancing method of  claim 16  wherein the positioning operations each comprise:
 rotating the one or more nozzles about an axis of rotation transverse to the reference plane to a first angle of the at least two different angles. 
 
     
     
         18 . The sludge lancing method of  claim 17  wherein the positioning operations each further comprise:
 translating the one or more nozzles using a translation mechanism that is separate from a mechanism for moving the one or more nozzles along the NTL. 
 
     
     
         19 . The sludge lancing method of  claim 17  wherein the positioning operations each further comprise:
 sighting the one or more nozzles along a tube lane to be lanced using a laser sight mounted with the one or more nozzles. 
 
     
     
         20 . A method comprising:
 positioning a nozzle assembly comprising a plurality of nozzles proximate a proximal end of a tube sheet bundle comprising a plurality of tubes;   positioning a first sensor proximate a distal end of the tube sheet bundle; and   aligning the nozzle assembly, wherein spray paths between each of the plurality of nozzles and the distal end of the tube sheet bundle are unobstructed by one or more of the plurality of tubes.   
     
     
         21 . The method of  claim 20 , wherein the nozzle assembly is positioned 90 degrees with respect to the tube sheet bundle. 
     
     
         22 . The method of  claim 20  further comprising positioning an additional nozzle assembly at a second position with respect to the tube sheet bundle. 
     
     
         23 . The method of  claim 21 , wherein the nozzle position is less than ninety degrees. 
     
     
         24 . The method of  claim 21 , wherein the nozzle position is greater than ninety degrees. 
     
     
         25 . The method of  claim 20  further comprising spraying water through the nozzle assembly at a first pressure. 
     
     
         26 . The method of  claim 25  further comprising measuring conductivity of the spraying water. 
     
     
         27 . The method of  claim 25 , wherein aligning the nozzle assembly is performed prior to spraying water through the nozzle assembly. 
     
     
         28 . The method of  claim 20 , wherein the nozzle assembly comprises at least one laser.